Photographic system with quaternary releaser

ABSTRACT

There is described a photographic system wherein development of an exposed photosensitive element with an aqueous alkaline photographic developing composition is effected in the presence of a compound which releases a quaternary in alkaline environment. Photographic products and processes utilizing such compounds are also disclosed.

BACKGROUND OF THE INVENTION

The application relates to a photographic system, including photographicproducts and processes, which utilize compounds capable of releasing aquaternary upon contact with an aqueous alkaline processing composition.The application also relates to novel compounds.

In various photographic systems for forming images, whether in black andwhite or in color, it is often desirable to include in the photographicfilm unit one or more of the various photographic reagents required fordevelopment and/or to enhance image quality. This practice extends toboth conventional systems for forming negative images and also tovarious systems such as diffusion transfer wherein a positive image insilver or in color is obtained. In many instances the photographicreagent may be contained initially in either the processing compositionapplied for development and image formation or in the film unit itself.The latter embodiment is typically preferred so as to reduce the numberof ingredients required in the processing composition. In otherinstances the particular photographic reagent desired is notsufficiently stable in alkali to provide the requisite shelf life forthe processing composition or the reagent is not compatible and/orreacts with another reagent in the processing composition and thereforemust be contained initially in the film unit. In still other instancesthe reagents must be provided at some particular time in the developmentprocess which requires that it be present in a specified layer or inspecified proximity to another layer in the film unit.

In all the foregoing instances it is desirable that the reagent becontained in the desired layer or layers of the film unit in a form thatis stable and non-migratory or non-diffusible and yet available when itis required at a particular time in the development process. Toaccomplish this result it is known in the art to attach to theparticular photographic reagent a blocking moiety which prevents thereagent from reacting with other photographic materials present in thefilm unit or migrating or diffusing prior to the time when photographicdevelopment is effected but which will release the photographic reagentat the desired time such as by reaction with the aqueous alkalineprocessing composition.

The present application relates to a photographic system whereindevelopment of an exposed photosensitive element is carried out in thepresence of a compound which provides a controlled release of aquaternary during the development process and to novel compounds.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a novelphotographic system.

It is another object of the invention to provide a system which utilizesa compound capable of releasing a quaternary during development of anexposed photosensitive element.

Still another object is to provide novel photographic products andprocesses.

Yet another object is to provide novel compounds.

BRIEF SUMMARY OF THE INVENTION

These and other objects and advantages are accomplished in accordancewith the invention by providing a photographic system whereindevelopment of an exposed photosensitive element with an aqueousalkaline processing composition is carried out in the presence of acompound represented by the formula ##STR1## wherein R₁ is --(CH₂)_(n)--R₂ ; R₂ can be hydrogen, alkyl, preferably having from 1 to 6 carbonatoms, or aryl such as phenyl or phenyl substituted with anyphotographically acceptable substituents such as electron withdrawinggroups, e.g., trifluoromethyl, cyano, fluorine, bromine, chlorine oriodine, etc., or electron donating groups such as alkyl, alkoxy, e.g.,methoxy and benzyloxy, amino, etc.; A is an aromatic group such asphenyl, naphthyl or phenyl or naphthyl substituted with any suitableelectron withdrawing or electron donating groups such as those describedabove; X is a photographically acceptable anion such as radicals ofbromine, N-toluene sulfonyl anthranilate, naphthalene sulfonate, laurylsulfate, and n is an integer of from 1 to 6.

Where R₂ is aryl, it is possible to change the release rate of thematerial by appropriately substituting the R₂ group. An electronwithdrawing substituent typically would increase the release ratewhereas an electron donating substituent typically will decrease therelease rate.

In a preferred embodiment A is ##STR2## where R₃ and R₄ can eachindependently be hydrogen, an electron donating group such as nitro,amino, alkyl, preferably having from 1 to 6 carbon atoms, alkoxy,preferably having from 1 to 6 carbon atoms, e.g., methoxy and benzyloxy,etc.; an electron withdrawing group such as any described above; or--NHSO₂ R₅ wherein R₅ can be alkyl, preferably having from 1 to 16carbon atoms or aryl such as phenyl or substituted phenyl; and m and pare each independently 0 or 1.

The substituent(s) on the aromatic ring A also affect the release rateof the compound. Generally, the electron donating group will increasethe release rate whereas the electron withdrawing groups decrease therate. It is preferred to substitute the ring in the para position and itis particularly preferred to do so with an electron donating group sincethis embodiment provides the fastest release. It should be noted thattypically the effect on the release rate of R₃ and R₄ is greater thanthat of substituents attached to R₂ when R₂ is aryl.

It is known in the art, as taught by U.S. Pat. No. 3,173,786 thatquaternary groups can function as development accelerators in diffusiontransfer photographic systems which utilize dye developers as the imagedye-providing materials. It is also disclosed that, in such systems,quaternary groups which include a reactive methyl group, i.e., a methylgroup which in alkali is capable of forming a methylene base, can alsoprovide improved color separation, i.e., the transfer of the dyedevelopers is more closely controlled by the silver halide emulsion withwhich each is associated. The compounds within Formula A cleave inalkaline compositions to provide a controlled release of such amethylene base.

The rate of release of the quaternary is dependent upon the hydroxyl ionconcentration of the processing composition used to process thephotographic elements and is also temperature dependent, that is, moreis released as the temperature at which processing of the photographicelement is effected rises.

BRIEF DESCRIPTION OF THE DRAWING

For a better understanding of the invention as well as other objects andfurther features thereof, reference is made to the following detaileddescription of various preferred embodiments thereof taken inconjunction with the accompanying drawing wherein the FIGURE is apartially schematic, cross-sectional view of one embodiment of a filmunit according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A class of preferred compounds for use according to the invention isrepresented by the formula ##STR3## wherein R₁, R₃, R₄, X, m and p areas previously defined. Specific preferred compounds within this formulaare:

    __________________________________________________________________________    COM-                                                                          POUND                                                                              R.sub.1     R.sub.3      R.sub.4            X                            __________________________________________________________________________          ##STR4##                                                                                  ##STR5##                       CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       2                                                                                   ##STR6##                (p)-OCH.sub.3      CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       3                                                                                   ##STR7##                (p)-NO.sub.2       CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       4                                                                                   ##STR8##                (p)-NHSO.sub.2 (CH.sub.2).sub.2 CH.sub.3                                                         CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       5                                                                                   ##STR9##   (O)OCH.sub.3                    CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       6                                                                                   ##STR10##  (O)OCH.sub.3                    Br.sup.⊖             7                                                                                   ##STR11##               (p)-NO.sub.2       Br.sup.⊖             8                                                                                   ##STR12##  (O)OCH.sub.3 (p)Br              CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       9                                                                                   ##STR13##                                                                                              ##STR14##         Br.sup.⊖             10                                                                                  ##STR15##                                                                                              ##STR16##         Br.sup.⊖             11                                                                                  ##STR17##               (p)-NO.sub.2                                                                                      ##STR18##                   12                                                                                  ##STR19##                                                                                              ##STR20##         Br.sup.⊖             13                                                                                  ##STR21##               (p)-NHSO.sub.2 (CH.sub.2).sub.15 CH.sub.3                                                        Br.sup.⊖             14                                                                                  ##STR22##                                                                                              ##STR23##         Br.sup.⊖             15                                                                                  ##STR24##               (p)-NHSO.sub.2 (CH.sub.2).sub.15 CH.sub.3                                                        Br.sup.⊖             16                                                                                  ##STR25##               (p)-OCH.sub.3      Br.sup.⊖             17                                                                                  ##STR26##  (O)OCH.sub.3                    CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       18                                                                                  ##STR27##                                  CF.sub.3 SO.sub.3.sup..cr                                                     clbar.                       __________________________________________________________________________

Another class of preferred compounds for use according to the inventionis represented by the formula ##STR28## wherein R₁ and X are aspreviously defined.

The compounds may be prepared according to reactions which are known tothose skilled in the art. Generally, the compounds can be made by thecondensation of picoline with an aldehyde in the presence of a basewhere required. Typically the picoline is initially reacted with butyllithium to give 2-picolyl lithium and the latter is reacted with theappropriate aldehyde followed by alkylation.

These compounds may be present in photographic elements in anyappropriate location and in any amount which is required to accomplishtheir intended purpose. The amount necessary in any particular instanceis dependent upon a number of factors such as, for example, the compoundutilized, the type of photographic element, the location of the compoundin the photographic element and the result desired. Routine scopingtests may be used to ascertain the concentration which is appropriatefor any given photographic element. According to a preferred embodimentof the invention there are provided diffusion transfer photographic filmunits as will be discussed more in detail below herein. In suchphotographic film units the compounds may be incorporated in thephotosensitive element and/or the image receiving element. The compoundsmay be used in any photographic system wherein the release of aquaternary during development of an exposed photosensitive element isdesired, including photographic systems for forming images in black andwhite or in color and those wherein the final image is a silver image orone formed by other image-forming materials. Further, where appropriate,the compounds may be utilized in various layers of a multilayerphotographic system in varying concentrations to ensure the desireddistribution of the quaternary during processing.

The compounds utilized according to the invention may be used inconjunction with any photographic emulsion. In a preferred embodimentthe compounds are utilized in diffusion transfer photographic systems,particularly those which include a negative working silver halideemulsion, i.e., one which develops in the areas of exposure. Further,these compounds may be used in association with any image dye-providingmaterials. In a particularly preferred embodiment the diffusion transferphotographic film elements of the invention include one or more imagedye-providing materials which may be initially diffusible ornondiffusible. In diffusion transfer photographic systems the imagedye-providing materials which can be utilized generally may becharacterized as either (1) initially soluble or diffusible in theprocessing composition but which are selectively rendered nondiffusibleimagewise as a function of development; or (2) initially insoluble ornondiffusible in the processing composition but which selectivelyprovide a diffusible product imagewise as a function of development. Theimage dye-providing materials may be complete dyes or dye intermediates,e.g., color couplers. The requisite differential in mobility orsolubility may be obtained, for example, by a chemical reaction such asa redox reaction, a coupling reaction or a cleavage reaction. In aparticularly preferred embodiment of the invention the imagedye-providing materials are dye developers which are initiallydiffusible materials. The dye developers contain, in the same molecule,both the chromophoric system of a dye and a silver halide developingfunction as is described in U.S. Pat. No. 2,983,606.

Other image dye-providing materials which may be used include, forexample, initially diffusible coupling dyes such as are useful in thediffusion transfer process described in U.S. Pat. No. 3,087,817 whichare rendered nondiffusible by coupling with the oxidation product of acolor developer; initially nondiffusible dyes which release a diffusibledye following oxidation, sometimes referred to as "redox dye releaser"dyes, described in U.S. Pat. Nos. 3,725,062 and 4,076,529; initiallynondiffusible image dye-providing materials which release a diffusibledye following oxidation and intramolecular ring closure as are describedin U.S. Pat. No. 3,433,939 or those which undergo silver assistedcleavage to release a diffusible dye in accordance with the disclosureof U.S. Pat. No. 3,719,489; and initially nondiffusible imagedye-providing materials which release a diffusible dye followingcoupling with an oxidized color developer as described in U.S. Pat. No.3,227,550.

In the diffusion transfer photographic film units of the invention aquaternary may be included in the processing composition and aquaternary-releasing compound within Formula A incorporated in thephotosensitive element. The quaternary which is released may be the sameas or different than the quaternary in the processing composition.

The compounds may be incorporated into the photographic elements by anysuitable technique. The compounds can be incorporated in thephotographic element typically by being coated from a water or oildispersion and the layer(s) in which they reside typically include abinder material such as gelatin or the like.

In a preferred embodiment of the invention, the compounds are utilizedin diffusion transfer photographic film units in conjunction withinitially diffusible dye developers as the image dye-providingmaterials. As described in U.S. Pat. No. 2,983,606 a photosensitiveelement containing a dye developer and a silver halide emulsion isphotoexposed and a processing composition applied thereof, for example,by immersion, coating, spraying, flowing, etc., in the dark. The exposedphotosensitive element is superposed prior to, during, or after theprocessing composition is applied, on a sheet-like support element whichmay be utilized as an image-receiving element. In a preferredembodiment, the processing composition is applied to the exposedphotosensitive element in a substantially uniform layer as thephotosensitive element is brought into superposed relationship with theimage-receiving layer. The processing composition, positionedintermediate the photosensitive element and the image-receiving layer,permeates the emulsion to initiate development. The dye developer isimmobilized or precipitated in exposed areas as a consequence of thedevelopment. In unexposed and partially exposed areas of the emulsion,the dye developer is unreacted and diffusible and thus provides animagewise distribution of unoxidized dye developer, diffusible in theprocessing composition, as a function of the point-to-point degree ofexposure of the silver halide emulsion. At least part of this imagewisedistribution of unoxidized dye developer is transferred, by imbibition,to a superposed image-receiving layer or element, said transfersubstantially excluding oxidized dye developer. The image-receivinglayer receives a depthwise diffusion, from the developed emulsion, ofunoxidized dye developer without appreciably disturbing the imagewisedistribution thereof to provide a reversed or positive color image ofthe developed image. The image-receiving element may contain agentadapted to mordant or otherwise fix the diffused, unoxidized dyedeveloper. In a preferred embodiment of said U.S. Pat. No. 2,983,606 andin certain commercial applications thereof, the desired positive imageis revealed by separating the image-receiving layer from thephotosensitive element at the end of a suitable imbibition period.Alternatively, as also disclosed in said U.S. Pat. No. 2,983,606, theimage-receiving layer need not be separated from its superposed contactwith the photosensitive element, subsequent to transfer image formation,if the support for the image-receiving layer, as well as any otherlayers intermediate said support and image-receiving layer, istransparent and a processing composition containing a substance, e.g., awhite pigment, effective to mask the developed silver halide emulsion oremulsions is applied between the image-receiving layer and said halideemulsion or emulsions.

Dye developers, as noted in said U.S. Pat. No. 2,983,606, are compoundswhich contain, in the same molecule, both the chromophoric system of adye and also a silver halide developing function. By "a silver halidedeveloping function" is meant a grouping adapted to develop exposedsilver halide. A preferred silver halide development function is ahydroquinonyl group. In general, the development function includes abenzenoid developing function, that is, an aromatic developing groupwhich forms quinonoid or quinone substances when oxidized.

Multicolor images may be obtained using dye developers in diffusiontransfer processes by several techniques. One such techniquecontemplates obtaining multicolor transfer images utilizing dyedevelopers by employment of an integral multilayer photosensitiveelement, such as is disclosed in the aforementioned U.S. Pat. No.2,983,606 and in U.S. Pat. No. 3,345,163, wherein at least twoselectively sensitized photosensitive strata, superposed on a singlesupport, are processed, simultaneously and without separation, with asingle common image-receiving layer. A suitable arrangement of this typecomprises a support carrying a red-sensitive silver halide emulsionstratum, a green-sensitive silver halide emulsion stratum and ablue-sensitive silver halide emulsion stratum, said emulsions havingassociated therewith respectively, for example, a cyan dye developer, amagenta dye developer and a yellow dye developer. The dye developer maybe utilized in the silver halide emulsion stratum, for example, in theform of particles, or it may be disposed in a stratum behind theappropriate silver halide emulsion strata. Each set of silver halideemulsion and associated dye developer strata may be separated from othersets by suitable interlayers, for example, by a layer or stratum ofgelatin or polyvinyl alcohol. In certain instances, it may be desirableto incorporate a yellow filter in front of the green-sensitive emulsionand such yellow filter may be incorporated in an interlayer. However,where desirable, a yellow dye developer of the appropriate spectralcharacteristics and present in a state capable of functioning as ayellow filter may be so employed and a separate yellow filter omitted.

Particularly useful products for obtaining multicolor dye developerimages are disclosed in U.S. Pat. No. 3,415,644. This patent disclosesphotographic products wherein a photosensitive element and animage-receiving are maintained in fixed relationship prior to exposure,and this relationship is maintained as a laminate after processing andimage formation. In these products, the final image is viewed through atransparent (support) element against a light-reflecting, i.e., whitebackground. Photoexposure is made through said transparent element andapplication of the processing composition provides a layer oflight-reflecting material to provide a white background. Thelight-reflecting material (referred to in said patent as an "opacifyingagent") is preferably titanium dioxide, and it also performs anopacifying function, i.e., it is effective to mask the developed silverhalide emulsions so that the transfer image may be viewed withoutinterference therefrom, and it also acts to protect the photoexposedsilver halide emulsions from post-exposure fogging by light passingthrough said transparent layer if the photoexposed film unit is removedfrom the camera before image formation is completed.

U.S. Pat. No. 3,647,437 is concerned with improvements in products andprocesses disclosed in said U.S. Pat. No. 3,415,644, and discloses theprovision of light-absorbing materials to permit such processes to beperformed, outside of the camera in which photoexposure is effected,under much more intense ambient light conditions. A light-absorbingmaterial or reagent, preferably a pH-sensitive phthalein dye, isprovided so positioned and/or constituted as not to interfere withphotoexposure but so positioned between the photoexposed silver halideemulsions and the transparent support during processing afterphotoexposure as to absorb light which otherwise might fog thephotoexposed emulsions. Furthermore, the light-absorbing material is sopositioned and/or constituted after processing as not to interfere withviewing the desired image shortly after said image has been formed. Inthe preferred embodiments, the light-absorbing material, also sometimesreferred to as an optical filter agent, is initially contained in theprocessing composition together with a light-reflecting material, e.g.,titanium dioxide. The concentration of the light-absorbing dye isselected to provide the light transmission opacity required to performthe particular process under the selected light conditions.

In a particularly useful embodiment, the light-absorbing dye is highlycolored at the pH of the processing composition, e.g., 13-14, but issubstantially non-absorbing of visible light at a lower pH, e.g., lessthan 10-12. This pH reduction may be effected by an acid-reactingreagent appropriately positioned in the film unit, e.g., in a layerbetween the transparent support and the image-receiving layer.

The dye developers are preferably selected for their ability to providecolors that are useful in carrying out subtractive color photography,that is, the previously mentioned cyan, magenta and yellow. The dyedevelopers employed may be incorporated in the respective silver halideemulsion or, in the preferred embodiment, in a separate layer behind therespective silver halide emulsion, and such a layer of dye developer maybe applied by use of a coating solution containing the respective dyedeveloper distributed, in a concentration calculated to give the desiredcoverage of dye developer per unit area, in a film-forming natural, orsynthetic, polymer, for example, gelatin, polyvinyl alcohol, and thelike, adapted to be permeated by the processing composition.

Other diffusion transfer products and processes in which the dyedevelopers of the present invention may be utilized are described inU.S. Pat. Nos. 3,573,043 and 3,594,165. For convenience, the entiredisclosure of each of the six patents referred to immediately above ishereby incorporated by reference herein.

A particularly useful film unit according to the invention is onewherein the photosensitive element includes a light-reflecting layerbetween the silver halide layer and the image dye-providing materiallayer (as described in Canadian Pat. No. 668,592), the substrate of thephotosensitive element carries the polymeric acid neutralizing layerwhich in turn carries the timing layer (as described in U.S. Pat. No.3,573,043) and the processing composition includes an oximatedpolydiacetone acrylamide thickening agent (as described in U.S. Pat. No.4,202,694).

In the FIGURE there is shown another preferred diffusion transfer filmunit of the invention wherein the film unit 10 comprises a transparentsupport 14 carrying on a first side thereof a layer 12 of a transparentpolymeric material adapted to convert to an opaque condition whencontacted by an aqueous alkaline processing composition. On the opposedside of support layer 14 is shown a polymeric acid-reacting layer 16,timing layer 18, a blue sensitive silver halide emulsion layer 20, ayellow dye deeloper layer 22, an interlayer 24, a green sensitive silverhalide emulsion layer 26, a magenta dye developer layer 28, aninterlayer 30, a red sensitive silver halide emulsion layer 32, a cyandye developer layer 34, an interlayer 36, an opaque/reflective layer 38(which preferably contains a white pigment such as titanium dioxide toprovide a white background against which the image is viewed and anopacification agent such as carbon black), an image receiving layer 40and an anti-abrasion layer 42.

Photoexposure of the silver halide emulsion layers is effected throughthe transparent polymeric layer 12 and through transparent support 14and the layer carried thereon, i.e., the polymeric acid layer 16 and thespacer or timing layer 18, which layers are also transparent, the filmunit being so positioned within the camera that light admitted throughthe camera exposure or lens system is incident upon the outer orexposure surface 12a of the polymeric layer 12.

After photoexposure, the film unit is developed such as by immersing itin an aqueous alkaline processing composition. After a suitableimbibition period, e.g., in the range of about 40 to 120 seconds, thetransparent polymeric layer 12 is converted by the alkaline processingcomposition to a highly colored, or opaque, layer. In addition,development of emulsion layers 20, 26 and 32 is initiated by contactwith the processing composition. If the film unit is removed from theprocessing composition to conditions of ambient light, the stillphotosensitive and developing emulsion layers thereof are protectedagainst additional photoexposure by ambient and environmental lightthrough transparent support 14 by the now opaque layer 12. The emulsionlayers are protected against additional photoexposure from the opposed,or image-viewing, side of the film unit by opaque reflective layer 38.

In exposed and developed areas, the dye developers are oxidized as afunction of the silver halide development and are immobilized.Unoxidized dye developer associated with undeveloped and partiallydeveloped areas remains mobile and is transferred to the image-receivinglayer 40 to provide the desired positive image therein.

Permeation of the alkaline processing composition through the severallayers of the film unit is controlled so that the process pH ismaintained at a high enough level to effect the requisite developmentand image transfer and to convert polymeric layer 12 to a highly coloredform after which pH reduction is effected as a result of alkalipermeation into the polymeric acid layer 16 such that the pH is reducedto a level which stops further dye transfer. Layer 12, after having beenrendered opaque by the action of alkali, remains opaque notwithstandingthis pH reduction. The image present in image-receiving layer 40 isviewed though the anit-abrasion layer 42 against the reflecting layer 38which provides an essential white background for the dye image and alsoeffectively masks from view the developed silver halide emulsion layersof dye developer immobilized therein or remaining in the dye developerlayers.

In the embodiment illustrated in the FIGURE image receiving layer 40 andreflecting layer 38 against which the image is viewed are shown aslayers of the film unit 10. While this is a particularly useful andpreferred embodiment, image formation can be accomplished in a separateimage receiving element comprising a transparent or opaque (e.g.,baryta) support and an image receiving layer. The image receivingelement may be brought into superposed relation with a photosensitiveelement comprising layers 12 through 38, either before or afterphotoexposure thereof. Polymeric layer 12 can be rendered opaque anddevelopment can be initiated by contact with an aqueous alkalineprocessing composition. The image-receiving element can be left intactfor viewing through the transparent support thereof, a reflection printagainst reflective layer 38. Alternatively, the image-receiving elementcan be separated for a viewing of a transparency or reflection print,respectively in the case of a transparent or opaque image-receivingelement support.

According to another embodiment, transparent polymeric layer 12 can, ifdesired, be positioned between transparent support 14 and polymeric acidlayer 16. It will be appreciated, however, that owing to the amount oftime required for alkali to permeate the several layers of the film unitso as to permit conversion of the transparent layer 12 to an opaquelayer, the positioning shown in the FIGURE is preferred. A quaternarynitrogen-containing polymer suitable for use in layer 12 is disclosed inU.S. Pat. No. 4,452,878.

It should be noted here that other opacification systems may be used inlayer 12. Further, it should also be recognized that photoexposure andprocessing of the film unit can be carried out in the dark in which caselayer 12 is not required.

The invention will now be desired further in detail with respect tospecific preferred embodiments of way of examples, it being understoodthat these are illustrative only and the invention is not intended to belimited to the materials, conditions, process parameters, etc., whichare recited therein.

EXAMPLE I

A stainless steel bomb containing p-nitrobenzaldehyde (300 g, 1.99moles), α-picoline (650 ml, 6.59 moles) and distilled water (100 ml,5.56 moles) was sealed and held in an oil bath at 140°-160° C. for 19hours. It was cooled to room temperature and opened to the atmosphere.The contents of the reactor, a mass of crystals and some dark liquid,were added to one liter of a 60:40 methanol-water mixture and theresulting mixture stirred for two hours. The solid was recovered byfiltration, washed with one liter of the same solvent mixture and driedunder vacuum at 50° C. to give 383-396 g (79%-82% yield) of ##STR29##4-nitrophenyl-(α-picolyl)carbinol.

The carbinol (210 g, 0.86 mole) was suspended in one liter of CF₃ CH₂ OHalong with 5 g of 10% Pd-C and the mixture agitated with a mechanicalrocker under 6 atmospheres of hydrogen for 30 hours. The mixture wasthen filtered through diatomaceous earth and the filtrate evaporatedunder vacuum. The crude solid product was recrystallized from hot ethylacetate to give 143 g (77% yield) ##STR30## as off-white prisms.

The amine (188 g, 0.88 mole) was stirred in 750 ml of pyridine at 0° C.under a calcium sulfate drying tube. Tosyl chloride (170 g, 0.885 mole)was added to the solution in solid portions over 11/4 hours. Whenaddition was complete the reaction mixture was stirred at roomtemperature for one hour and then slowly poured into 8 liters ofdistilled water with vigorous stirring. The product was collected bysuction filtration, washed with approximately 2 liters of water and thenwith 95% ethanol and pressed to remove solvent. The solid was thenrecrystallized twice from hot 95% ethanol to give 284 g (88% yield) of4-p-toluene sulfonamidophenyl-(α-picolyl)-carbinol ##STR31## as whiteplates.

The 4-p-toluene sulfonamidophenyl-(α-picolyl)-carbinol (123 g, 0.338mole) was suspended in 400 ml of sulfolane and stirred aso-methylbenzylbromide (64 g, 46.3 ml, 0.345 mole) was added in a singleportion. The resulting suspension was heated to 80° C. with stirringunder nitrogen for 21/2 hours during which time the solid dissolved andthen reprecipitated turning yellow in color. The suspension was cooledsomewhat and ethyl acetate (1.25 liters) was added with stirring. Thesolid was isolated by suction filtration and pressed to remove solvent.The solid was resuspended with stirring in 750 ml of acetonitrile andfiltered again. The solid was washed with 50% acetonitrile-methanol,then with acetonitrile and finally with diethyl ether and vacuum driedat room temperature to give 135 g (72% yield) of ##STR32## a pale yellowpowder.

The structure of the product was confirmed by a ¹³ C NMR spectrum.

NMR [CDCL₃, (CD₃)₂ S=O] δ 2.19 (3H, S), 2.22 (3H, S); 3.25 (2H, n); 4.9(1H, br t); 5.95 (2H, s); 6.4 (1.H, d, J=8 Hz); 6.7-8.2 (13H, n); 8.34(1H, t, J=7 Hz); 8.8 (1H, d, J=7 Hz); 9.9 (1H, s).

The mass spectrum showed a cation with m/e=473.

EXAMPLE II

As a control a film unit was prepared by coating on a transparentsubcoated polyethylene terephthalate film base the following layers:

1. an antistatic layer made up of about 500 mg/m² of sodium cellulosesulfate and about 150 mg/m² of potassium chloride;

2. a polymeric acid layer of approximately 9 parts by weight of a 1/2butyl ester of polyethylene/maleic anhydride copolymer and 1 part ofpolyvinyl butyral coated at a coverage of about 16000 mg/m² ;

3. a timing layer coated at a coverage of about 2500 mg/m² of a34-30-15-14-4-3 hexapolymer of diacetone acrylamide (DAA), butylacrylate (BA), carbomethoxymethyl acrylate (CMA), ethyl acrylate (EA),acrylic acid (AA) and methyl methacrylate (MMA);

4. a blue sensitive silver iodobromide emulsion layer comprising about598 mg/m² of silver (0.2 micron), about 299 mg/m² of silver (0.5micron), about 598 mg/m² of silver (1.3 microns) and about 746 mg/m² ofgelatin;

5. a yellow dye developer layer comprising about 1000 mg/m² of a yellowdye developer represented by the formula ##STR33## about 489 mg/m² ofgelatin; about 100 mg/m² of 4'-methylphenylhydroquinone; and about 30mg/m² of the methyl ethyl sulfone adduct of phenylmercaptotetrazole;

6. an interlayer made up of a 35-29-15-14-4-3 hexapolymer ofDAA/BA/CMA/EA/AA/MMA coated at a coverage of about 1500 mgs/m², about 17mgs/m² of succindialdehyde and about 23 mgs/m² of polyvinylpyrrollidone;

7. a green sensitive silver iodobromide emulsion layer comprising about358 mgs/m² of silver (0.2 micron), about 179 mgs/m² of silver (0.5micron), about 358 mgs/m² of silver (1.3 microns) and about 448 mgs/m²of gelatin;

8. a magenta dye developer layer comprising about 450 mgs/m² of amagenta dye developer represented by the formula ##STR34## about 286mgs/m² of gelatin, about 69 mgs/m² of 4'-methyl phenylhydroquinone andabout 30 mgs/m² of the methyl ethyl sulfone adduct ofphenylmercaptotetrazole;

9. an interlayer comprising about 2000 mgs/m² of the hexapolymer oflayer 6, about 21 mgs/m² of succindialdehyde and about 60 mgs/m² ofpolyvinyl pyrrolidone;

10. a red sensitive silver iodobromide emulsion layer comprising about289 mgs/m² of silver (0.2 micron), about 289 mgs/m² of silver (0.5micron) about 289 mgs/m² of silver (1.3 microns) and about 433 mgs/m² ofgelatin;

11. a cyan dye developer layer comprising about 425 mgs/m² of a cyan dyedeveloper represented by the formula ##STR35## about 320 mgs/m² ofgelatin, about 121 mgs/m² of 4'-methylphenylhydroquinone, about 41mgs/m² of the methyl ethyl sulfone adduct of phenylmercaptotetrazole andabout 25 mgs/m² of the cyclohexanoneoxime adduct ofphenylmercaptotetrazole;

12. an interlayer made up of a 37-30-14-11-5-3 hexapolymer ofDAA/BA/EA/CMA/AA/MMA coated at a coverage of about 11 mgs/m² ofsuccidialdehyde and about 30 mgs/m² of polyethyleneoxide;

13. an opacification layer comprising about 1000 mgs/m² of carbon blackand about 275 mgs/m² of gelatin;

14. a reflection layer comprising about 11000 mgs/m² of titaniumdioxide, about 1433 mgs/m² of polyethylene oxide, about 403 mgs/m² ofgelatin, about 2200 mgs/m² of a 60-30-4-6 tetrapolymer of butylacrylate, diacetone acylamide, styrene and methacrylic acid and about1433 mgs/m² of Teflon 30®, a water based dispersion ofhexafluoropropylene/tetrafluoropropylene copolymer particles;

15. an image receiving layer coated at a coverage of about 2000 mgs/m²of a graft copolymer comprising 4-vinylpyridine (4VP) and vinyl benzyltrimethylammonium chloride (TMQ) grafted onto hydroxyethylcellulose(HEC) at a ratio HEC/4VP/TMQ of 2.2/2.2/1, about 370 mgs/m² of gelatinand about 667 mgs/m² of a dihexyl ester of sodium sulfosuccinic acid;and

16. a topcoat layer of about 500 mg/m² of gelatin.

The film unit was exposed (12 mcs) in the dark to a test exposure targetthrough the support and then laminated together with a processingelement made up of a 4 mil thick corona treated polystyrene supporthaving coated thereon.

1. a layer made up of about 1500 mgs/m² of a copolymer of 3 parts4-vinyl pyridine and 1 part vinyl benzyl trimethylammonium chloride andabout 27 mgs/m² of 1,4-butanediol diglycidyl ether; and

2. a layer made up of about 3500 mgs/m² of kappa carrageenan, about 1512mgs/m² of sodium hydroxide, about 1414 mgs/m² of potassium hydroxide andabout 63,608 mgs/m² of water.

The laminate was allowed to remain in the dark for about five minutesand the red, green and blue D_(max) and D_(min) values for the neutraldensity columns were read on a densitometer.

A second control film unit was prepared and processed in the same mannerwith the only exception being that layer 2 of the processing element wasmade up of about 3500 mgs/m² of kappa carrageenan, about 1890 mgs/m² ofsodium hydroxide, about 883 mgs/m² of potassium hydroxide, about 850mgs/m² of phenethyl alpha-picolinium bromide and about 62,900 mgs/m² ofwater.

Film Units A and B according to the invention were prepared. These wereidentical to Control I except that the topcoat layer (16) of thephotosensitive element included 1200 mgs/m² and 1400 mgs/m²,respectively, of compound 10. The film units were processed as describedabove with a processing element such as that used to process Control I.

    ______________________________________                                        FILM UNIT           R          G    B                                         ______________________________________                                        CONTROL I    D.sub.max                                                                            2.13       2.53 2.63                                                   D.sub.min                                                                            0.23       0.23 0.47                                      CONTROL II   D.sub.max                                                                            1.99       2.35 1.91                                                   D.sub.min                                                                            0.19       0.21 0.28                                      A            D.sub.max                                                                            1.99       2.45 2.26                                                   D.sub.min                                                                            0.21       0.21 0.25                                      B            D.sub.max                                                                            2.00       2.56 2.28                                                   D.sub.min                                                                            0.20       0.21 0.26                                      ______________________________________                                    

The background areas of the Control I film unit had a yellowish colorthereby indicating that the yellow dye developer was not completelycontrolled by the associated silver halide emulsion in the absence of aquaternary. The background areas of the Control II film unit were freeof any yellow color showing that the quaternary in the processingcomposition had dramatically assisted in control of the yellow dyedeveloper. The red, green and blue D_(max) values for Control II wereall significantly less than the corresponding values for Control I andthe D_(min) values were smaller, the blue being significantly smaller,showing that the quaternary assisted in the control of all three dyedevelopers.

The background areas of film units A and B were virtually the same inappearance as those of Control II which indicates that the releasablequaternary compound of the invention was able to dramatically assist inthe control of the yellow dye developer. Further, it can be seen thatthe green and blue D_(max) values of both film units A and B were higherthan the corresponding values for Control II with approximately the sameD_(min) values.

Although the invention has been described in detail with respect tovarious preferred embodiments thereof, these are intended to beillustrative only and the invention is not limited thereto but ratherthose skilled in the art will recognize that modifications may be madetherein which are within the spirit of the invention and the scope ofthe appended claims.

What is claimed is:
 1. A photographic element comprising a support andat least one layer thereon containing a silver halide emulsion havingassociated therewith a compound represented by the formula ##STR36##wherein R₁ is --(CH₂)_(n) --R₂ ; R₂ is hydrogen alkyl or aryl; A is anaromatic group; X is an anion; and n is an integer of from 1 to
 6. 2.The photographic element as defined in claim 1 wherein A is phenyl,naphthyl, substituted phenyl or substituted naphthyl.
 3. Thephotographic element as defined in claim 2 wherein R₁ is ##STR37## and Ais phenyl or substituted phenyl.
 4. The photographic element as definedin claim 3 wherein A is ##STR38## wherein R₃ and R₄ each independentlyis hydrogen, nitro, amino, alkyl, alkoxy, or --NHSO₂ R₅ ; R₅ is alkyl oraryl; and m and p each independently is 0 or
 1. 5. A photographicproduct for use in forming a multicolor diffusion transfer imagecomprising a photosensitive element comprising a support carrying ablue-sensitive silver halide emulsion having a yellow imagedye-providing material associated therewith, a green-sensitive silverhalide emulsion having a magenta image dye-providing material associatedtherewith and a red-sensitive silver halide emulsion having a cyan imagedye-providing material associated therewith, a second sheet-like elementpositioned in superposed or superposable relationship with saidphotosensitive element, an image receiving layer positioned in one ofsaid elements, a rupturable container releasably holding an aqueousalkaline processing composition adapted, when distributed between a pairof predetermined layers carried by said photosensitive element and saidsecond element, to develop said silver halide emulsions and provide amulticolor diffusion transfer image on said image receiving layer, atleast one of said photosensitive and second elements including acompound represented by the formula ##STR39## wherein R₁ is --(CH₂)_(n)--R₂ ; R₂ is hydrogen alkyl or aryl; A is an aromatic group; X is ananion; and n is an integer of from 1 to
 6. 6. The photographic productas defined in claim 5 wherein A is phenyl, naphthyl, substituted phenylor substituted naphthyl.
 7. The photographic element as defined in claim6 wherein R₁ is ##STR40## and A is phenyl or substituted phenyl.
 8. Thephotographic element as defined in claim 7 wherein A is ##STR41##wherein R₃ and R₄ each independently is hydrogen, nitro, amino, alkyl,alkoxy or --NHSO₂ R₅ ; R₅ is alkyl or aryl; and m and p eachindependently is 0 or
 1. 9. A diffusion transfer photographic elementcomprising a transparent support carrying a photosensitive systemcomprising a silver halide emulsion layer in association with an imagedye-providing material layer and an image receiving layer, saidphotosensitive system including a compound represented by the formula##STR42## wherein R₁ is --(CH₂)_(n) --R₂ ; R₂ is hydrogen alkyl or aryl;A is an aromatic group; X is an anion; and n is an integer of from 1 to6.
 10. The photographic element as defined in claim 1 wherein A isphenyl, naphthyl, substituted phenyl or substituted naphthyl.
 11. Thephotographic element as defined in claim 10 wherein R₁ is ##STR43## andA is phenyl or substituted phenyl.
 12. The photographic element asdefined in claim 11 wherein A is ##STR44## R₃ and R₄ each independentlyis hydrogen, nitro, amino, alkyl, alkoxy or --NHSO₂ R₅ ; R₅ is alkyl oraryl; and m and p each independently is 0 or
 1. 13. The photographicelement as defined in claim 9 as further including an opacificationlayer comprising an initially transparent layer which is adapted tobecome opaque upon contact with a photographic aqueous alkalineprocessing composition, said opacification layer being positioned on theside of said transparent support opposite that which carires thephotosensitive system.
 14. The photographic element as defined in claim13 and further including on the side of said support which carries saidphotosensitive system a reflective layer adapted to the viewingthereagainst of a photographic imate in said image receiving layer.